Device for regulating the thickness of ice formations on evaporator coils



June 10, 1947; c. E. VANDENBERG 2,421,319 r l I DEVICE FOR REGULATINGTHE THICKNESS OF ICE FORMATIONS ON AN EVAPORATOR COIL Filed June 10,1942 2 shuts-spent 1 Jun; 10, 1947. c. VANDENBERG DEVICE FOR REGULATINGTHE THICKNESS OF ICE FORMATIONS ON AN EVAPORATOR COIL FiledJunelO, 19422 Sheets-Sheet 2.

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Patented June 16, i947 STATE navrcn FOR-REGULATING rm emptiness 0F ICEFORMATHONS 0N UDILS wiarence E. landcnberg, or to International Haporation of New Jersey Application June lid, 1942, Serial No. M6520 f 14Claims (Cl 6) This invention relates to a regulating device and moreparticularly to a device for use with an apparatus for altering surfaceformations, whereby the regulating device controls or regulates theoperation of said apparatus in the formation or alteration of thesurface.

The invention is especially adapted for use in a device for regulatingthe thickness of an ice bank'to be formed on the coils of arefrigerator.

In the ordinary refrigerating machine of: one i provided a plurality ofa particular type, there refrigerating coils which are immersed in atank These coils have refrigerant passed therethrough for the purpose ofcreating an ice bank to cool the water, the tank of water thus servingas i a 'cooling receptacle. In such instances,it is desirable to controlthe operation of the refrigerator according to the size or thicknessofthe ice bank formed on the coils Various devices have heretofore beenemployed for this purpose. However, these deviceshave been found to begenerally defective in that they are' not accurately responsive to theformation of the ice bank on the coils. According to the presentinvention, there is provided an improved regulating device designed torespond immediately to the attainment of a predetermined or desiredthickness of an ice bank, and, being so responsive, to cut ed theoperation of the refrigerating mechanism.

As will be hereinafter pointed out, the prin-,

ciples'of'the invention may be embodied in devices for use with othertype of apparatus that may function to, alter or form or otherwiseaffect the dimensions of an article or an element, itbeing obvious thatother elements or articles may be subjected to changes similar to theincrease in sizeof an'ie bank,

The principal object of the present invention is to provide an improvedregulating, or control device for the purposes set forth above.

An important object of the invention is to provide a, regulating devicehaving a contactor arm movable through a range including as one of itslimits, a point designating a desirable position or other characteristicof a surface or element'to be formed or otherwise affected.

Figure 2 showing the contactor arm lator in one position of itsoperation before the formation, of a desired ice bank;

Blue Island, Ell, assignrv ester Company, a cor Another object oftheinvention is to provide a I regulating device which is automatic inoperation in response to the alteration of a surface, such as theincrease to a predetermined sizeof an ice bank, and which device maypermit operation of the refrigerating compressor or, other apparatuseven though the ice bank has reached its desired thickness.

Another object is to provide the regulating device with an electricalcontrol system.

Other objects and desirable features of the invention will becomeapparent as th disclosure of the invention is more fully made in thefollowing description and accompanying sheets of drawings. in which:

Figure l is a view of a preferredform of the v Figure 6 is a similarview showing the contactor in another position of its movement;

Figure 7 is a similar view showing the contactor arm as'afiected by theultimate thickness of the ice bank and the resultant operation of thecontrol switch;

Figure 8 is a fragmentary detail view taken on the line 8-8 of Figure 2showing the association between parts of the contactor arm; and

Figure 9 is a fragmentary view showing in section the relation betweenthe contactor arm and carrier structure, as viewed along the-lin 9- 9 ofFigure 5.

One form of refrigerating apparatus with which the regulator may be usedis illustrated in the patent to Borgerd et al. 2,077,871, April 20,1937.

It is an important object of the invention to,

utilize the movabl arm or equivalent means in conjunction withregulating the maximum thickness of an ice bank in, a refrigeratingmachine, whereby the contactor does not have permanent contact with theice bank, thus eliminating the possibility that the ice bank will buildup around the contactor. i

For the purposes of the present, disclosure, reference is had tothatpatent for adetailed illustration of the parts of the refrigerator.However, Figure 4 of the present case illustrates those parts oftheapparatus thought necessary for the disclosure of the structure andoperation of, the present invention, In that figure,' I0 indicates theupper portion, or coverof 'atank or cabinet ,for

a refrigerator. A supporting table is mounted sectional view taken onthe cabinet l and carries an electric motor l2, a compressor l3, acondenser l4. and an agitating pump I 5. The motor drives the compressorin the usual manner to force refrigerant through tubes or pipes" 16which lead to a plurality of coils forming a refrigerating .unit aroundthe inside of therefrigerating cabinet l9. Parts of these coils or tubesare designated in other figures by the numeral As-indicated generally inFigures 1 and 5 to 7, inclusive, the coils function to form an ice bankindicated generally at I 8. As shown in the patent referred to above,the coils are immersed in water contained in the refrigerating cabinetor tank, and operation of the refrigerating system results in theformation of an ice bank completely around the inside of therefrigerator. The space delineated by the ice bank is adapted for thereception of articles to be refrigerated. Y I I As previously stated, animportant object of the present invention is to provide means for theregulation of the size or thickness of the ice bank l8 formed on thecoils H. A preferred embodi ment of the invention comprises a regulatingdevice which is mounted on the top of the cabinet ID. This structure isbest shown in Figure 1.

The regulating or control device comprises an upper support 9 secured tothe top of the cabinet I0 and having a depending bracket 29 projectingthrough an opening 2| in the top of the cabinet. The bracket is rigidlysecured at its upper end to the support I9, and its lower end isprovided with a lug 22 adapted to engage an end or side wall of thecabinet III, as at 23. This arrangement provides a rigid constructionand maintains the position of the device in the cabinet.

The support l9; rigidly carries a vertically disposedplate 24 and alsocarries a driving means in the form of a small electric motor 25. Theplate is apertured at its center, and a driving shaft 26 driven by therotor of the motor 25 through extensive reduction gearing extendstherethrough. At the side of the plate opposite the motor 25 the drivingshaft 26 fixed to run counter-clockwise viewing it as in Figure 1carries a crank member 21 in the form of a U-shaped member, as bestshown in Figure 3. The direction of rotation of the shaft 26 may beclockwise depending on the arrangement of the associated elements. Thecrank and the shaft 26 may have relative angular movement to a limitedextent, and the shaft carries a driving pin 28 which extends at oppositesides of the shaft to abut the bight portion of the U-shaped member 21,as best shown in Figure 5. The crank has pivoted at one end thereof adriving link 29. The other endof, the link is pivoted by a pin 30' to.theupper end of a vertically extending carrier arm 3|. This arm extendsdownwardly and is mounted on the bracket 20 by means of a transversepivot pin 32.

As best shown in Figure 9, the carrier arm 3|- is of channelconstruction. The arm serves to carry a second or contactor arm 33, thissecond arm being also mounted on the pivot pin, 32. The arms 3| and 33are mounted for relative movement about the pivot pin 32, and both 'armsas a unit may pivot about the pin 32 with respect to the bracket 20. Thearm 33 is likewise of channel construction and is disposed within thechannel a of thearm 3|. The upper end of the arm 33, is resilientlyconnected to the upper end of the arm 3|, preferably by means of aheaded rod 34 which passes through both arms and which carries a smallcompression spring 35 operable to expand between an abutment 36 'on therod 34 and an electrical switch 38 preferably constructed as a platemember 39 mounted on the pin 30 and a sealed, non-conducting tube 40mounted bn the plate 39 by clips 4| The tube preferably contains aquantity of mercury, as indicated by the dotted line at 42 in Figure 1.At spaced portions near the right end of the tube 40 there is provided apair of depending tubular portions 43, each of which is connected in anelectrical circuit, as will presently appear. The mercury 42 in the tube4|! connects the portions 43 and provides a conductor between theseportions.

The electrical circuit for the operation of the regulating device isillustrated diagrammatically in Figure 4. The tubular portions 43 of thetube 40 are connected to electrical leads 44 and. 45, and thus acomplete circuit is established. between a source of electrical energythrough the switch 3|! and the-motor l2 for operating the refrigeratingsystem. As is also shown in this figure. the small electric motor 25 isconnected inparallel 'with'this circuit by leads 46. From thedescription thus far it will be seen that the refrigerating system isoperable continuously as long as. the

between. the leads that enter the tubular portions 43. As will bedescribed below, the regulating device is operable to break this circuitin response to a predetermined thickness attained by the formation ofthe icebank on the coils Theplate 39, which mounts the switch 38 on theupper end of the: arm 3 I, is provided with an integral dependingportion 41, the lower end of which is slotted and engageable with a pin48 carried at the upper end of the second or contactor arm 33. Aspreviously stated. the arms 3| and 33 may have relative movement,thismovement being ordinarily resisted by action of the small spring 35.One of the sides off the arm 3|, is provided with an arcuate slot 49which permits free operation of the pin.'48* when the arms have relativemovement. This structure is best shown in Figure 8.

From the description thus far, it will. be seen that with the switch 38closed the motors l2 and 25 operate, the former to drive the compressorand agitating pump and the latter torotate the.

' shaft 26 very slowly; Because of the linkage comprising the crank 21and link 29., rotation of the shaft 26 causes rocking of the arms 3| and33. These arms rock very slowly and in unison until the ice bank reachesthe predetermined thickness, at which time the contact inthe switch 38is broken and the refrigerating system stops. A further and moredetailed description of the operation of the control means will be setforth below.

portion of this plunger is disposed directly above the linkagecomprising the crank 21 on the shaft 26 and the connecting link 23. Therelationship 5 of these parts is best indicated in Figures 1 and2,

- and the position of the lower portion of the plunger 52 is shown inbroken lines in Figure 7.

The plunger is thus operable to be pressed downwardly on the over-centerparts 2'! and 29 so that the crank 21 rotated with respect to the shaft26.

tive rotation is permitted because of may be This relathe looseconnection between the shaft and the crank.

linkage formed by the in which the switch will close v above, andthrough the medium of tubes or pipe lines 53 is'adapted to agitate thewater in the cabinet Ill. The tubes 53 extend downwardly toward thebottom-of the tank and cause. air bubbles to rise banks.

In the operation of the is closed, closing the electrical circuits toboth the motor l2 and the motor 25. The refrigerator 1 then operatesnormally. As the refrigerating system continues to operate,-ice banksare formed on the coils or tubes II, as previously described. when theice bank is comparatively thin, as illustrated in Figure 5, the arms 3!and 33 move back and forth in unison, driven by the small motor 25. Thisrepeated movement of the arm is comparatively slow point of providing anaccurate determination of the proper thickness of the ice bank. If thearms were so arranged as to be stationary with respect to the ice bankbeing formed, it would be found that the ice would build up around thecontact point 31 so that'the bank would attain a considerable thickness,even beyond that desired, before the control device would operate. It isaccordingly preferred that the arms move back and forth, as described.

is unaffected, the slow rocking movement being insufflcient to upset thecontact or connection formed by the mercury 42. When the ice bankreaches the desired thickness, as indicated in Figure 7, continuedmovement in a counter-clockwise direction about th pivot 32 is resisted;but, since the motor 25 continues to operate, the arm 3| is-pivoted withrespect to the arm'33, the resilient connection 35 permitting thisrelative movement. Now,' since the slotted arm or leg 47 on theswitch-carrying plate 39 is engaged by the transverse pin 48 in 26 movesthe arm 3| and switch 38 to the left with respect to the arm 33.Thereupon the angular movement of the tube 48 is in a counterclockwisedirection to the extent that the contact or connection provided by themercury 42 is broken, the mercury flowing to, the left end of the tube40 and hence out of the depending contact 43 at the extreme right end.As shown in Figure 6, the mercury tub 48 is also tilted, but

connected at the time when the tube 48 is tipped in the water adjacentthe me As the arms slowly oscillate or pivot, the switchof the arm 3'3Inasmuch as both dependin device, the switch so gardless. of the size ofbeing accomplished by downwardly to the 1eft,-the motor 2! is' stopped-and the linkage comprising the link 21 and link 28 assumes the positionshown in Figure 7, with the pivot axis of the snaftf26 an pivot pin 30in alinement with the pivotal connection between the link 23and thecrank 21. Thus, the

switch 38 is held in disconnected position. At the same time, the mainmotor l2 is-cut out and the refrigeration of the compartment byoperation of the motor ceases.

Certain conditions exist when it is desired to. operate the motor l2regardless of the fact that a suflicient ice bank hasbeen formed on thecoils or tubes l1. Such a condition may exist when the agitator t5,whichis Ordinarily, such opera- 1 it is desired to operate driven by themotor l2. tion would be impossible as long as. the switch 38 opened bythe position of the arms 3| and 3 as assumed upon contact of the contactarm; or desired ice bankthick- 33 with apredetermined ness. However, theswitch 38 may-be closed rethe ice bank-,this result the actuation of thesp ing-Dressed plunger 52. e I

Figure 7 illustrates the parts in the position assumed thereby when theice bank has reached its proper thickness. It willbe noted from an:

examination of this figure, in conjunction with an examination ofFigural, that the dower por-- I tion of the plunger 52 is directly abovethe connection move the link 29 downwardly an to rotate the and isimportant from the stand- 3 crank 21 with respect to the motor shaft 26.As stated previously, this relative rotation is permitted because of theloose I between the motor shaft 26 and vcrank 21 by the driving pin 28.In short, pressure on the plunger- 52 serves to pivot "the switch 38back to a position in which the mercury 42 can complete the circuitbetween the contacts in the spaced tubular portions 43. Consequently,the motor I 2 may be driven fora short period. This period is hereinmeasured by one complete revolution of the motor shaft 28, after whichbe restored to the positions shown in Figure "I,

at which time the switch 38 will again be opened.

, sired thickness.

the arm 33, continued rotation of the motor shaft It will be seen fromthe foregoing description that the present form of the regulating deviceinof the automatic operation effected by the thick- Figure 7 it istipped angularly clock- 48, the mercury. I

ness of the ice bank. This control is not designed so as to permitexcessive operation of the refrigerating system to an extent that themechanism will be damaged, but the independent control of the switch isprovided solely for the purpo e of operating the motor l2-for shortperiods. Tlfe entire device is so constructed as to be capable of readyinstallation in a refrigerating cabinet, for which use it is especiallyadapted; although, as previously stated, the device may also be adaptedfor use in conjunction with other and similar types of apparatus and theuse of the device is necessarily limited to the control of refrigeratingapparatus. g i

between the motor shaft 26 and the car 1 rier arm 3|. Pressure on theplunger serves to connection effected the parts will In addition, theswitch 7 The foregoing description of the invention will undoubtedlysuggest various modifications and uses in the preferred form of theinvention shown denser, of a device for controlling the operation ofsaid apparatus to llmitthe size of ice formations on said evaporator;said device comprising a contactor adapted to move repeatedly to andfrom-a predetermined position to be reached by ice forming on' thesurface of said evaporator, a movable carrier for the contactor, meansfor moving the carrier to move the contactor rebecause of greater thandesired thickness of the ice bank, and means connected with thecontactor and the carrier so as to be responsive to relative movementtherebetween to stop the carrier moving means and the contactor.

4. The combination, with a tank for holding a cooling liquid 'and'arefrigeration system including an evaporator in the tank in position tobe submerged by liquid therein, of a device for peatedly to and from thesaid predetermined position, means resiliently connecting the contactorand the carrier to permit relative movement therebetween upon contact ofthe contactor with an ice formation projecting from said surface to thesaid predetermined position, and means actuated by relative movementbetween the carrier and contactor to stop operation of thecarrier-moving means and to stop the operation of said motor.

'2. The combination with refrigerating apparatus including a compressor,a motor for operating the same, a. condenser and an evaporator incircuit with said compressor and said condenser, of a device forcontrolling the operation of said apparatus to limit the size of iceformations on said evaporator; said device comprising a contactoradapted to move repeatedly to and from a predetermined position to bereached by ice forming on the surface of said evaporator, a movablecarrier for the contactor, means receiving electrical current from asource of power for moving the carrier to move the contactor repeatedlyto and from the said predetermined position, means resilientlyconnecting the contactor and the carrier to permit relative movementtherebetween upon contact of the contactor with an ice formationprojecting from said surface to the said predetermined position, andmeans actuated by the relative movement between the contactor andcarrier to stop the flow of electrical current to the carrier-movingmeans and to the motor to stop the operation of the carrier-moving meansand to stop the operation of the compressor.

3. The combination, with a tank for holding a coolin liquid and arefrigeration system lnclud ing an evaporator in the tank in position'tobe submerged :by liquid therein, of a device for limiting the size of anice bank building up on said evaporator, saiddevice comprising acontactor having one end extending into the portion normally occupied bythe cooling liquid and adapted to move repeatedly to and from apredetermined position reached by the surface of theice bank when thelatter attains the desired thickness, a movable carrier for thecontactor,

means for repeatedly moving the carrier to move the contactor repeatedlyto and from the said predetermined position, means resilientlyconnecting the contactor and the carrier to permit relative movementtherebetween upon contact by the contac'torwith the surface of the icebank limiting the size of an ice bank building ullon said evaporator,said device comprising a first armhavingoneendextendingintotheportion"normally occupied by the cooling liquid in the tank and the other endprojecting from the top of the tank, means including a pivot oonnectinstheflrstarmtothetopofthetaninasecond arm pivotally mounted on the samepivot and having one end extending into a position nor-- mally occupiedby such cooling liquid and ear-..- rying a contactor adapted to contactthe sur-' face of the ice bank on the evaporator and the other endprojecting from the top or the tank, electrically-driven means mountedon the top of the tank connected with the arms to move the first arm andin unison therewith the contactor on the second arm repeatedly to andfrom a predetermined position reached by the surface of the ice bankwhen the latter attains the desired thickness, means resiliently holdingthe second 30' arm in a certain relation with respect to the first armand permitting movement of the second armaway from the certain relationupon contact by the contactor with the surface of the ice bank beyondthe predetermined position because of greater than desired thickness ofthe ice bank, and an electrical switch for controlling saidelectrically-driven means and so associated with the arms projectingfrom the tank as to be responsive to the second arm's being in thecertain relation with respect to the first arm to close and so as to beresponsive to th second arms being removed from the certain relationwith respect to the second arm to open.

5. The combination in a refrigeration system including an evaporator, ofa device for limiting the size of an ice bank building up on saidevaporator, said device comprising a contactor adapted to moverepeatedly to and from a predetermined position reached by a surface ofthe ice bank when the latter attains the desired thickness, a support,an arm rockably mounted on the support and carrying the contactor, anelectric motor mounted on the support, means connecting the motor andthe arm to rock the arm to move the contactor repeatedly to and from thesaid predetermined position, the meanscomprising a rotating crankconnected with the arm and permitting movement of the contactor awayfrom the certain relation upon contact by the contactor with the surfaceof the ice bank formed beyond the predetermined position, an electricalswitch for controlling said electric motor and so associated with thearm and the contactor as to be responsive to the contactors beingremoved from the certain relation with respect to the arm to open.

formed beyond the said predetermined position 15 the connecting rodjoining the crank and the arm whereby, upon opening'of the electricalswitch due to movement of the contactor away from" the certain relationwith respect tothe arm upon contacting the ice. bank, the crank may,without turning of the motor. bemoved angularly to move the arm andcontactor away from the ice bank to permit the contactor to return to"said certain relation with respe to th arm by virtue of which relationthe switch is closed for passage of electrical current therethrough.

7. A combination such as set forth in claim 5, in which there is alost-motion connection between the electric motor and the crankconnected thereto, whereby, without rotation of the motor, the crank maybe moved angularly. to move the connecting rod joining the crank and thearm whereby, upon opening of the electrical switch due to movement ofthe contactor away from the certain relation withrespect to the arm uponcontacting the ice bank, the crank may, without turning of the motor, bemoved angularly'to movethe arm and contactor away from the ice bank topermit the contactor to return to the certain relation with respect tothe arm by virtue of which relation the switch is closed for passage ofelectrical current therethrough, the lost-motion connection being formedby virtue of the fact that the electric motor has a shaft mounting thecrank for relative angular movement, the crank has an elongated slot,and a driving pinprojects into the shaft and into the elongated slot' inthe crank.

8. The combination with a tank for holding articles to be cooled and arefrigerating system including an evaporator located in said tank, of adevice for limiting the thickness of an ice formation on saidevaporator, said system including an electrically operated unit forliquefying refrigerant and forcing it from said unit to and through saidevaporator for cooling thereof, and said evaporator being so located insaid-tank as to leave a space between itself and a wall of said tank anda second space for said articles; said device comprising a first armhaving one end extending into'the first-mentioned space and the otherend projecting above the tank, a second arm having one end extendinginto the first mentioned space and carrying a contactor and the otherend projecting above the tank, means pivotally mounting the arms on thetank, an electric motor connected with the first arm for moving thearms-repeatedly back and forth to bring the contactor to and from apredetermined posi-' tionreached by the surface of the ice bank when thelatter attains the desired thickness, means resiliently yieldablyconnecting the second arm in a certain relation with respect to thefirst arm and permitting movement of the second am away from the certainrelation upon contact by the contactor with the surface of the ice bankbeyond the said predetermined position because of greater than desiredthickness of theme bank, an electrical switch for controlling saidelectrically operated unit and said electric motor and'so associatedwith the ends of the arms above the tank as to be responsive to thesecond arms being in the certain relation to the first arm to close andthereby to pass'current'to the motor and to the electrically operatedunit for moving the arms back and forth and for cooling the evaporator,and so as to be responsive to the second arm's being removed from thecertain relation to open and thereby to stop the'flow of current to themotor and the electrically operated unit for stopping the movement ofthe arms of the evaporator.

and the cooling y when said feeler is 9. The combination with arefrigerator comprising an evaporator, a condenser, a compressorconnected to said evaporator and said condenser and a first motor foroperating said compressor, of a regulator for controlling the size of,an ice bank forming on said evaporator; said regulator comprising ai'eeler movable to and from a predeterminedlimit point adjacent theevaporator; a second motor for reciprocating said feeler; an electricalcircuit having said second motor wired in parallel with said firstmotor, an electrical switch in the circuit arranged to be actuatedprevented from reaching its predetermined limit point adjacent theevaporator by ice forming th'ereon. a

10. The device specified in claim 9, the said electrical switch being anon-conducting closed tube having a pair of depending tubular portionspositioned near one end of said tube and a quantity of mercury containedin the tube and depending tubular portions.

11. A refrigerator comprising, in combination, a compressor, acondenser, and an evaporator,

- means for controlling the operation. of said com.-

pressor, comprising a contactor adapted to move repeatedly to and from apredetermined position to be reached by formations growing on thesurface or the evaporator, a movable carrier for the contactor, meansdriven by electricity for operating the compressor, means driven byelectricity for causing the carrier to move the contactor repeatedlytoward and away from the said predetermined position, means resilientlyconnecting the contactor to the carrier in a certain relation withrespect to the carrier and permitting relative movement of the carrieraway from the said certain relation upon contact of the contactor with asurface formation beyond the said predetermined position, an electricalswitch associated with the carrier and the contactor so as to beresponsive to the contactors being in the said certain relation withrespect to the carrier to close and thereby to cause the switch tocomplete the circuit of current to both the aforesaid driven means, andso as to be responsive to the contactors being removed from the saidcertain relation with respect to the carrier to open and therea by tointerrupt the flow of current to both, the

aforesaid driven means.

12. The device specified in claim 11, the said electrical switch being anon-conducting closed tube and a quantitylof mercury contained in thetube.

13. A-refrigerator comprising, in combination,

a compressor, a condenser, and an evaporator,

means for :controlling the operation of said apparatus, comprisingasupport, a firstarm, means pivotally mounting the first arm on thesupport so as to be movable back and forth, a second arm, means mountingthe second arm for pivotal movement with respect to the first arm, meansresiliently holding the second arm in a certain relation relative to thefirst arm so as to cause movement of the first arm back and forth tobring the second arm to and from a predetermined position and to permitmovement of the second arm relative to the first arm away from the saidcertain relation upon contact by the second arm with a surface formationgrowing on and extending from said evaporator beyond the saidpredetermined position, electrical means for op-' erating thecompressor, electrical means for moving the first arm back and forth tobring the sec- .ond arm to and away from the said predeterminedposition, an electrical switch associated with said arms whereby thesecond arms being in the certain relation with respect to the first armholds the switch closed and thereby completes the circuit or current tomove the arms and to operate the compressor, and whereby the secondarm's being removed from the said certain relation with respect to thefirst arm holds the switch open and thereby interrupts the flow ofcurrent to both the aforesaid driven means.

14. The device specified in claim 11, the said electrical switch being anon-conducting closed tube having a pair. of depending tubular portionspositlonednear one end of said tube and a. quantity 0!.mercury containedin the tube and de-' pending tubular portions.

The following references are of record in the file of this patent: v

UNITED STATES PATENTS Number Date Name Bell July 5, 1938 Schweitzer July9,' 1935

